Only specific account, or will it be possible to use wildcards to match a domain?

With wildcards.
Basically, the condition will match the parameter to the "authenticated account name" attribute of the queue file (on the 'S' line when that is available), the same way as parameters are matched in other similar conditions. The absence of that attribute will match the empty string.

The new From Address editor allows anyone to create multiple identities and easily change the From addresses of outgoing emails.

However, I don't think the pre-6.2 UserFrom setting changed the Return-Path of the message. This one does.

Previously I had a rule with a "Return Path is *@mydomain". Since all my users are authenticated, the Return-Path was always reliable. Now it doesn't apply anymore for webmail messages when the user changes his From address.

How can I apply outgoing rules based on the account that sent the message?

In 6.2.3 later this month the Authenticated condition will be available in mail rules to check if message submission was authenticated with specific account.

--
Best regards,
Dmitry Akindinov

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